A national bird conservation organization says grassland habitat loss on the Prairies has created a "conservation crisis" for dozens of species of birds.

The crisis is illustrated in a new State of Canada's Birds report published Tuesday by Birds Canada in partnership with Environment and Climate Change Canada.

It says that since 1970, when dependable bird count data started being kept, birds living full or part time in Prairie grasslands have declined by 67 per cent.

Birds that live primarily or only in Prairie grassland areas have declined by 90 per cent over that same time period, the report shows.